Liquid applicator system



July 1, 1969` R. G. HENTSCHEI.

` LIQUID APPLICATOR'SYSTEM Filed June 6, 1967 Sheet NIQNBW INVENTORRUDOLF G. HENTSCHEL BY @MM Il '.4 .1l

ATTORNEYS `uly 1, 1969 R. G. HENTscHEl.

LIQUID APPLICATOR SYSTEM Sheet Filed June 6, 1967 Mfg MUIINW" TACH INPUTINVENTOR TIG. 4 RUDQLF G. HENTSCHEL MOTOR com' RoLLER Box l l ATTO R NEYS United States Patent Oftice 3,452,710 Patented July 1, 19693,452,710 LIQUID APPLICATOR SYSTEM Rudolf G. Hentschel, Ann Arbor,Mich., assignor to Baker & Gubbins Co., Clawson, Mich., a corporation ofMichigan Filed `lune 6, 1967, Ser. No. 643,992 Int. Cl. B05c .l1/02;B05b 7/06, 13/02 U.S. Cl. 118-7 12 Claims ABSTRACT OF THE DISCLOSURELiquid applicator apparatus for applying lubricants and rust inhibitorsto strip or sheet metals being processed in rolling mills or the like. Aliquid applicator is positioned transversely above the path of travel ofthe metals and a plurality of solenoid operated discharge valves arespaced across the header. Remote control switches are provided forselectively varying the number of valves that are open or closed, and anelectronic switch is provided which is responsive to the rate of travelof the conveyor for the metals for opening or closing all of the valvessimultaneously if the conveyor speed is above or below a predeterminedmagnitude, and the rate of discharge of the liquid `also is controlledas a function of the rate of travel of the conveyor.

CROSS REFERENCE TO RELATED APPLICATION This application relates to theliquid applicator system of copending application Ser. No. 588,967, ledOct. 24, 1966, now Patent No. 3,402,695 and assigned to the assignee ofthe present application. The present application contains improvementsover the liquid applicator system of the pending application.

BACKGROUND OF THE INVENTION The persent invention relates to a liquidapplicator system for use in applying liquids to sheet metal and stripworkpieces of a variety of widths which are being processed in rollingmills or the like, and the invention is directed in particular to animproved applicator header for use in the system as Well as to improvedcontrols for regulating the operation of the applicator header.

As is pointed out in the prior copending application, a variety ofliquids are employed in industry to aid in the processing of materials.Typical examples in the metal processing industries are the applicationof oils when metals are to be reduced in size, to be cleaned, or to beprepared for storage. Thus, hot rolled strip and sheet metals arefrequently treated with rolling lubricants, and rust inhibitors are alsoapplied to such workpieces. Similarly, in the reducing processes of coldrolled sheet and strip metal, lubricants and/or cleaning agents areapplied prior to annealing of the metal.

The procedures commonly followed today for carrying out operations ofthis character normally involve employing a liquid reservoir containingthe liquid or fluid to be applied, and such reservoir is placedsuiiciently high, so that it may feed the applicator header by gravity,the header being located in a position over a conveyor which is used tomove the workpieces. The header consists essentially of a `steel tubeequipped with spigots which dispense fiuid by gravity onto theworkpieces passing below on the conveyor. The spigots are equipped withknobs permitting manual adjustment or stopping of the flow of liquids.The workpieces to be coated are passed below the header by means of theconveyor, and normally the spigots are fully or partially open so thatliquid falls upon the workpieces as they pass.

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The liquid not clinging to the workpieces or conveyor is normally notrecovered and reused, because the required filtering and otherrecovering procedures needed would make the operation uneconomical.

The procedures used heretofore have a number of shortcomings. The factthat the liquid source for supplying the header is normally placed abovethe header is both inconvenient and impractical, particularly when it iskept in mind that the workpieces that are being passed under the headermay change in width on frequent occasions during a normal working shiftin the steel mills. The conveyor width represents the limit of themaximum width of a workpiece that can pass under the header, and theheader, therefore, in order to meet its intended purpose, must have awidth sulicient to allow 4a liquid distribution to cover the entirewidth of the conveyor. Under these conditions, the liquid is wasted ifthe workpiece has a width which is less than the full width of theconveyor, unless certain spigots are manually closed. It is found inpractice that the operators or workmen along the conveyor do notfrequently close the spigots which are not needed, and consequently awaste of the liquid occurs.

Another shortcoming of the existing system is that the liquid will bedispensed continually and at a substantially constant rate -regardlessof the rate of movement of the conveyor. Thus, if the conveyor shouldstop for any reason, the liquid will continue to be dispensed as long asthe liquid reservoir and header contains such a liquid. Again, it isrecognized that the spigots could be closed, but it is frequently foundthat because of the inaccessibility of the header, the workmen do notclose such spigots each time a stoppage of the conveyor occurs.

Since the conveyor does stop frequently during a normal work shift, therate of speed of the conveyor will also vary frequently, that is, duringacceleration and deceleration phases associated with the stop. At thesetime periods, the liquid dispensation will occur, because the rate ofliquid flow has ybeen set to correspond to the proper liquid coverage onthe metal or workpiece at maximum conveyor speed.

Thus, it is apparent that a great waste of coating liquid is associatedwith the systems now employed in the industry for coating workpieces,because the :shutdown time and acceleration and deceleration timeperiods comprise a substantial percentage of the time associated withthe normal metal processing operations, and during such time periods andduring the shutdown periods, substantial amounts of liquid are dispensedwhich are wasted or are in excess of that required for coating theworkpieces. This waste is in addition to the waste that occurs due tothe lack of width control of the header outlet. Furthermore, no controlof the liquid flow rate exists, which means that no correction can bemade to change the rate of liquid flow in case the combination ofgravity feed and header and spigot design fails to coincide with themaximum required rate of liquid flow at maximum conveyor speed. Theseshortcomings also create the additional problems that the operator mayset the spigots .at positions well below the position required atmaximum conveyor speed in order to reduce the waste of liquid in theshutdown time periods as well as in the time periods of deceleration andacceleration of the conveyor.

The invention disclosed in the aforesaid copending application Ser. No.588,697 overcomes the shortcomings of the perior art structuresdiscussed above, in that it discloses a header mounted transverselyabove the conveyor having outlet means for discharging liquid onto theworkpieces carried by the conveyor, and the header has a valvingarrangement for selectively varying the effect of transverse width ofliquid discharged from the header. The header also contains means forsimultaneously opening or closing all of said discharge outlets so thatthe entire system can Ibe interrupted simultaneously, if this isdesired. This invention also discloses puunp means for pumping liquid tothe header, and regulating means responsive to movement of the conveyorare provided for interrupting operation of the pumping means if thespeed of the conveyor falls below `a predetermined amount and forvarying the rate of liquid iiow from the header in accordance with therate of travel of the conveyor.

The system disclosed in the present application is similar to that setforth in the aforesaid copending application, in so far as the generaloperation is concerned. However, the present invention discloses aheader of substantially different construction having an entirelydifferent valving system, and also a separate and independent type ofelectrical control system is provided for remotely controlling theoperation of the header and its valves. Also, improved means areprovided for controlling the quantity of liquid delivered to the header.

According to a preferred form of the present invention, ya liquidapplicator system is provided having a liquid applicator header adaptedto be mounted transversely over a conveyor for transporting workpieces,and having a plurality of spaced solenoid operated valves fordischarging a liquid across the width of the conveyor, there beingprovided a liquid supply means for maintaining liquid in the applicatorheader, and remote control means for selectively opening and closing thesolenoid operated valves. The control ymeans include rotary switches foropening the solenoid operated valves sequentially from the center areatoward each end of the header so that the operator can selectively Narythe width of coverage of the liquid being discharged onto the workpiecescarried by the conveyor. An electronic control switch is also responsiveto movement of the conveyor for starting or interrupting flow of liquidthrough the header in accordance with the Speed of movement of theconveyor. A controller is provided for the pumping means and isresponsive to a tachometer associated with the conveyor whereby the rateof output of the pumping means is proportioned to the conveyor speed. Aby-pass valve arrangement is also provided to enable the operator toselect the desired quantity of liquid that is to be delivered to theheader.

It is an object of the present invention to provide a liquid applicatorsystem for use in processing workpieces of various widths, which has animproved uid distribution header and valving, and'in addition which hasimproved remote control means for supplying the liquid to the workpiecesat controlled rates and to desired areas of the conveyor system.

Other objects of the invention will appear in the following descriptionand appended claims, reference being had to the accompanying drawingsforming a part of this specification wherein like reference charactersdesignate corresponding parts in the several views.

In the drawings:

FIGURE 1 is ai schematic diagram of a preferred embodiment of theinvention, showing a conveyor in transverse section for movingworkpieces during rolling mill operations, and also showing the generalcomponents of the system embodying the invention;

FIGURE 2 is an enlarged fragmentary section of one end of the headertaken on the line 2-2 of FIGURE 3;

FIGURE 3 is a section of the header, taken on the line 3 3 of FIGURE 2;and

FIGURE 4 is a schematic wiring diagram of the electrical controls foroperation of the system.

Before explaining the present invention in detail, it is to beunderstood that the invention is not limited in its application to thedetails of construction and arrangement of parts illustrated in theaccompanying drawings, since the invention is capable of otherembodiments and of being practiced or carried out in various ways. Also,it is to be understood that the phraseology or terminology employedherein is for the purpose of description and not of limitation.

Referring now to the drawings, the invention will be described ingreater detail. The liquid applicator system 10 will be described rstwith respect to the general arrangement of parts shown in FIGURE l. Asthere shown, a conveyor belt 12 adapted for carrying workpieces at therolling mill is shown, and supported on the stationary supports 14 abovethe belt 12 is the applicator header assembly 16. A plurality ofdischarge nozzles 18 are arranged in spaced relationship across theentire width of the header assembly 16 so as to permit discharge ofliquid from the header 16 onto the conveyor belt 12. A reservoir 20 isprovided for storage of the liquid to be applied, and the reservoir 20is in communication -with a positive displacement gear pump 22 throughthe suction line 24. Coupled ot the pump 22 for driving the same is theadjustable speed electric motor 26. The gear pump 22 is of a type ysothat the volumetric output of the pump varies linearly with the rate ofrevolution at which it is driven 'by the adjustable speed electric motor26, and the pump 22 and motor 26 comprise a liquid supply means formaintaining liquid in the applicator header 16. Thus, the output of thegear pump 22 is connected by a conduit 2.8 to the inlet side of theheader 16. The discharge line 28 is also provided with an adjustableorifice valve 30 for selectively limiting the peak ow rate of liquidthrough the header 16.

Also forming a part of the liquid supply system is the by-pass valve 32lwhich is a conventional adjustable pressure relief valve which servesto by-pass liquid discharged from the gear pump 22 and in cooperationwith valve 30 is utilized to set the desired rate of tiow of liquid fromheader 16 onto metal products being conveyed by the conveyor 12. Safetyvalve 34 is also provided in the circuit so that if any malfunction orother condition occurs, resulting in the pressure in line 28 exceeding adesired maximum, valve 34 will open and by-pass liquid from the pump toreservoir 20.

The adjustable smed electric motor 26 is electrically connected to themotor controller 'box 36 by the cable 38. The controller box 36 receiveselectrical signals through cable 40 from a tachometer 42 which isresponsive to the rate of movement of conveyor 12, and controller box 36is also electrically connected to the system control box 44 by cable 46.Another electric cable provides electrical connection between the systemcontrol box 44 and the header assembly 16 for operating the solenoidoperated valves 18.

The header assembly 16 in which the solenoid operated valves 18 arelocated comprises a compartment S0 which normaily is completely closedwith the exception of the inlet provided for receiving liquid from theconduit 28 and the plurality of outlets 52 which communicate directlywith the solenoid operated valves 18. If desired, an air fitting 52, seeFIGURE l, may also be provided for venting the compartment or forintroducing high pressure air to blow out the compartment 50, if thisshould be desired.

Mounted 'below the compartment 50 is a panel housing 54 on the yback ofwhich are mounted the solenoid operated valves 18. As shown in FIGURE 3,the electrical leads 56 from the solenoid operated valve 18 extendthrough openings in the housing S4 to a panel 58 which is electricallyconnected with the conduit 48. The details of the solenoid operatedvalves 18 will not be described, since these valves are conventional inconstruction. Each of the valves employed in the present invention aretwoway normally closed valves, which are opened when the associatedsolenoids are energized. Discharge orices 60 are provided vfrom each ofthe valves for discharging a thin stream of liquid onto the surface ofworkpieces being carried by the conveyor 12.

Attention is next rdirection to FIGURE 4 for a brief description ofcertain of the electrical circuits employed in the present invention.

The electrical system is connected to a line voltage at 62 by theconductors `64 through the control switch 66 to the transformer 68. Thelatter steps down the line voltage to a level suitable for operation ofthe solenoid valves 18. In a preferred embodiment of the invention thevoltage is stepped down to 24 volts. The secondary of the transformer isconnected to the coils 70` of the solenoid valves 18, and it will benoted that a total of 35 such coils are provided, one for each solenoidoperated valve. The number of such valves will depend upon the size ofinstallation involved, and in the present embodiment there are threesets of such solenoid operated valves, one including the live valves inthe midportion of the header, which are identified by the numbers 0, 1and 2 in FIG- URE 4; the second set representing num-bers 3 through 17inclusive on the right side of the series of coils, and the third setrepresenting numbers 3 through 17 on the left side of the coils 70illustrated in FIGURE 4. The coils 70 in the rst set 72 are energizedvia conductors 76 and 78, when normally open relay operated switch 74 isclosed. The second set of the coils 70 are adapted to be energized inthe same manner, but this must be done through the rotary switch 80.Similarly, the third set of coils 70 can be energized by use of therotary switch 82. 'Ihe rotary switches 80 and 82 are operated from theexternal side of the system control box 44, as shown in FIG- URE 1.

The normally open relay operated switch 74 is controlled by theelectronic switch 84 which is conventional in construction and will bedescribed generally.

The electronic switch 84 is connected by means of cable 40 to receivefrom tachometer 42 an input voltage across lines 86. The switch `84 alsoreceives an alternating current voltage from the secondary oftransformer 64 via conductor 88. The diodes D1, D2, D3 and D4 condensersC1 and C2, and resistors R1 and R2 generate the direct current tooperate the amplitiers 90 which is operated as a voltage comparator andreceives signals from the tachometer across lines 86. An adjustable biasvoltage is obtained from variable resistor R3, and in the presentembodiment this adjustable bias range voltage is set to be from zero tove percent of the maximum tachometer input voltage. If the tachometerinput voltage exceeds the bias voltage the amplifier 90 ouput voltagewill switch from a negative ten volts to a plus ten volts to turn thesilicon controlled rectifier on, thereby energizing the relay operatedswitch 74. If the amplifier 90 again goes negative ten volts, thesilicon controlled rectifier 92 turns itself olf when the voltage on itsanode goes negative. The diode D serves to limit the maximum inputvoltage to plus ten volts and thus protects the amplier 90.

Thus, the electronic switch 84 operates to open and close the switch 74in response tol the tachometer input voltage across lines 86. This inputvoltage reflects the rate of travel of the conveyor 12. Normally theswitch 74 will be closed by electronic switch 84 when the conveyor 12 istraveling at or above tive percent of its maximum rate of travel. Whenthe rate of travel is below live percent of maximum, the tachometerinput voltage to electronic switch 84 will drop below that required tokeep switch 74 closed, and the latter will open, resulting in all ofcoils 70 of the solenoid operated valves 18 being deenergized, therebysimutlaneously closing all of the normally closed valves which may havebeen open.

As previously indicated, the iive valves 18 in the rnidportion of theheader 16 which comprise the lrst set of valves, will always beenergized and thereby open when switch 74 is closed. Also, the same willbe true of those valves in sets two and three which are controlledrespectively, by rotary switches 80 and 82, and whose coils areenergized because of the positions of such rotary switches. Thus, withrespect to the group two valves, the rotary switch 80 is closed withrespect to solenoid operated valves 3 through 12, on the right side; andwith respect to the group three valves, the rotary switch 82 is closedwith respect to the solenoid operated valves 3 through 9, on the leftside. Obiously, additional valves can be closed on the right side byrotating switch in a clockwise direction, and additional valves could beclosed on the left side by rotating switch 82 in a counterclockwisedirection. Thus, the operator can sequentially close or open the valveson either side of the conveyor 12 to vary the effective coverage of theliquid being discharged. Furthermore, whatever effective coverage thathas been established will be under the control of the electronic switch84 so that all valves which provide the desired coverage will be openedor closed simultaneously in response to action of the electronic switch84.

The tachometer input also is utilized to control the rate of pumping ofthe gear pump 22. As shown in FIG- URE 4 conductors 94 are connected tothe motor controller box 36 and across the tachometer input lines 86.The motor controller is conventional in construction, and in response tochanges in the voltage input from conductors 94 will change the motoreld, and therefore, the motor speed. This, of course, will then directlyaffect the ouput of the positive displacement gear pump 22.

In normal operation of the present invention, the operator willinitially set the rotary switches 80 and 82 so as to provide the desiredcoverage of liquid discharge onto the conveyor 12. The mill is thenstarted, and when the mill speed reaches ve percent of maximum speed,the electronic switch `84 will change state, thereby closing switch '74.This will have the efect of energizing those of the solenoid operatedvalves which have been selected for opening so that liquid can flowtherethrough.

Simultaneously with starting the mill, the motor 26 will be energized torotate at its idling speed so as to slowly turn the gear pump 22. Atthis initial starting, the solenoid operated valves 18 are still closedand the header assembly 16 will be lled with liquid and the pressure inline 28 will rise to a level determined by the setting of the by-passvalve 32, which setting will establish the volume of liquid beingreturned to the reservoir 20. The safety valve 34 will operate todischarge liquid to reservoir 20 only if a malfunction occurs in thesystem restricting the normal discharges from the header 16 and/ orreservoir 20.

When the speed of the mill rises above the live percent rate, thesolenoid operated valves selected to be opened will be energized byvirtue of action of electronic switch 84 so as to change them to theopen state, thereby allowing liquid to pass through the header assembly16 to the conveyor 12. The rate of liquid ow is also controlled by themagnitude of the tachometer signal by virtue of the connections 94 tothe motor controller box 36, which controls the rate of turning of themotor 26 and thereby the rate of liquid delivery from the gear pump 22.Thus, by proper setting of the valves 30 and 32 the proper quantity ofliquid will be discharged onto the workpieces on the conveyor 12,irrespective of the rate of travel of the conveyor 12. Also, propercoverage of liquid discharge from the header assembly 16 can readily beobtained by operation of selector switches 80* and 82. Still further,the valves selected to be open will be closed simultaneously when themill is stopped. This operation assures use of minimum quantities of theliquid while realizing optimum coverage of the workpieces. This systemof applying the liquids also eliminates undesirable atomization of theliquids and avoids undesirable dripping from the header.

Another signiiicant feature of the present invention is that it allowsthe operator to set the peak discharge of liquid to any desired amountwithout varying the normal controls of the motor 26 and gear pump 22 sothat for any peak discharge selected, the complete range of dischargefrom maximum to minimum output is realized in accordance with thesignals received by the motor con- 7 troller 36 from the tachometer `42.This setting of the peak discharge is obtained merely by making properselective settings of valves 30 and 32.

Thus, if it is `desired to discharge liquid from the header assembly 16at the peak rate of ten gallons per minute, the valves 30 and 32 will beset accordingly, and if the motor 26 has an effective speed range, forexample, of twenty to one, the pump 22 will discharge liquid at a rangeso that at maximum conveyor speed, the peak amount of ten gallons perminute will be discharged from header assembly 16, and at minimumconveyor speed onehal gallon per minute will be discharged from headerassembly 16. If different requirements of the liquid applicator shouldoccur, whereby the maximum or peak discharge of liquid from the headerassembly should be a lesser amount, such as tive gallons per minute, forexample, the valves 30 and 32 will be reset accordingly, and the sametwenty to one ratio of applying the liquid in response to the tachometer42 signals will still be realized so that atminimum conveyor speedone-quarter of a gal-` lon of liquid per minute will be discharged fromheader assembly 16.

Having thus described my invention, I claim:

1. In a liquid applicator system for use in processing Workpieces ofvarious widths wherein said workpieces are moved on a conveyor, theimprovement comprising a liquid applicator header adapted to be mountedtransversely of said conveyor and having a plurality of spaced solenoidoperated valves for discharging a liquid across the width of theconveyor, liquid supply means for maintaining liquid in said applicatorheader, and remote control means for selecting at least certain of saidsolenoid operated valves to be opened when the rate of travel of saidconveyor has risen to a preselected magnitude above the stationarycondition of the conveyor, said remote control means including meansresponsive to the rate of travel of said conveyor or openingsimultaneously all of said certain valves when the rate of travel ofsaid conveyor has risen to said preselected magnitude.

2. In a liquid applicator system, the combination according to claim 1,wherein said control means includes a rotary switch for opening saidsolenoid operated valves sequentially when rotated in one direction andfor closing said solenoid operated valves sequentially when rotated inthe other direction.

3. In a liquid applicator system, the combination according to claim 1,wherein said control means includes two separately operable switches onefor opening certain of said solenoid operated valves sequentially fromthe center area of said applicator header toward one end thereof, theother switch for opening certain of said solenoid operated valvessequentially from the center area of said applicator header toward theother end thereof.

4. In a liquid applicator ssytem, the combination according to claim 3,wherein said solenoid operated valves are in three sets, one setincluding the valves in the midportion of the header, the second setbeing controlled by said one switch and extending from one end of theheader to said midportion and the third set being controlled by saidother switch and extending from the other end of the header to saidmidportion.

5. In a liquid applicator system, the combination according to claim 3,wherein said control means includes a switch for closing and openingsimultaneously all of said certain solenoid operated valves.

6. In a liquid applicator system, the combination according to claim 3,wherein said control means includes a switch means responsive to therate of travel of said conveyor for closing simultaneously said certainsolenoid operated valves when the rate of travel of said conveyor dropsbelow a preselected magnitude.

'7. In a liquid applicator system, the combination according to claim 3,wherein said control means includes a switch means responsive to therate of travel of said conveyor for closing or opening simultaneouslysaid certain solenoid operated valves when the rate of travel of saidconveyor drops below or exceeds respectively a preselected magnitude.

8. In a liquid applicator system according to claim 1, wherein means areprovided for selectively adjusting the rate of flow of liquid trom saidsupply means to said certain valves for any selected rate o travel ofsaid conveyor.

9. In a liquid applicator system according to claim 1, wherein saidliquid supply means is responsive to the rate of travel of said conveyorfor synchronizing the rate of ow of the liquid to the rate of travel ofsaid conveyor.

10. In a liquid applicator system for use in processing workpieces ofvarious widths wherein said Workpieces are moved on a variable speedconveyor, the combination with said variable speed conveyor of a liquidapplicator header adapted to be mounted transversely of said variablespeed conveyor and having outlet means for discharging liquid across theeiective workpiece-carrying width of the variable speed conveyor, liquidsupply means for continuously delivering liquid from a source to saidapplicator header, means responsive to the rate of travel of saidvariable speed conveyor for regulating the rate of delivery of saidliquid supply means in proportion to the rate of travel of said variablespeed conveyor, adjustable means for allowing only selected portions ofthe proportioned liquid to be delivered to said header and control meansfor closing said outlet means when the rate of travel of said Variablespeed conveyor is at a preselected magnitude above the stationarycondition of said conveyor.

11. In a liquid applicator system, the combination according to claim10, wherein said control means is operable for selectively varying theetective width of liquid discharged from said header.

12. In a liquid applicator system the combination according to claim 11,wherein said control means is operable to initiate ow of liquid fromsaid header when the rate of travel of said variable speed conveyorrises above a preselected magnitude.

References Cited UNITED STATES PATENTS 2,804,764 9/1957 Runton 118-313 X2,960,060 ll/ 1960 Chatterton. 2,963,002 12/1960 Glaus 118-602 X WALTERA. SCHEEL, Primary Examiner.

JOHN P. MCINTOSH, Assistant Examiner.

U.S. Cl. X.R. 118-315, 324

